Evaluation of Different Enamel Reconditioning Techniques for Effective Orthodontic Bracket Rebonding

Aim: Aims and objectives of the study were to measure shear bond strength of rebonded orthodontic brackets after using different enamel reconditioning techniques including (Diamond bur, Air abrasion with Aluminum Oxide particles, Ultra Sonic scaler, CO2 laser ).Subjects and methods : This in vitro study consists of five groups with ten samples in each group. Each sample was bonded with a metal bracket. After debonding, reconditioning of the tooth surface was performed by the finishing Diamond bur, Air abrasion, Ultra Sonic Scaler and Fractional CO2 Laser . Rebonding of the reconditioned teeth was again performed. Universal testing machine was used to evaluate the shear bond strength of the orthodontic brackets. Enamel surface topography was evaluated using scanning electron microscope. Results: The maximum average score of shear bond strength was in the LASER Group (16.4 Mega Pascal ) (MPa) followed by Ultra Sonic Scaler (16.2MPa), The Control Group (14.9MPa), Sand blasting Group (14.6MPa), at last the Diamond Burs group (11.3MPa) . There was a relationship between surface roughness and the bond strength achieved. The method which created a smoother uniform surface achieved the higher shear bond strength. Conclusions: Fractional CO2 Laser, Ultra Sonic scaler and Air abrasion can be used as preferred method of reconditioning the tooth surface after bond failure instead of diamond burs to achieve optimal bond strength of rebonded brackets.